Robin and George. We'll talk to Steve ganyard about that in a minute. More on the questikquestions terry talked about. The unfolding investigation facing a number of daunting challenges. Brian Ross here with the latest. Reporter: Good morning, George. New details are expected later today from U.S. Intelligence agencies about the who and the what of the suspected attack on the jetliner. So far everything points to a group of Russian rebels who nato officials have been warning for the past month have been given some powerful weapons, weapons they may not fully understand how to use. Overnight, the rebels who are in control of the crash scene denied any responsibility for shooting down the plane. With the self-described prime minister of the rebels blaming the Ukrainian military saying his group's weapons aren't powerful enough to do so. Twice this week, the Russian rebels shot down two different kinds of Ukrainian military aircraft with their missiles. And now U.S. Officials believe the rebels mistakenly hit the Malaysian Boeing 777 aircraft while trying to target a third military plane on Thursday. Ukrainian officials made public a set of intercepted messages they say proves it. According to Ukraine a rebel commander first reported the plane had been shot down 30 minutes after it disappeared from radar but then a short while later as the first videos appeared online, Ukraine officials say the now shook up rebel commanders reported they were 100% sure it was a civilian aircraft, not military. Reporter: Are there any weapons, one person asks. Nothing at all. Civilian belongings, medical scraps, towels, toilet paper. Then told the mechanicage was clear it was a malyasian airliner. Another answer, well, then it was bringing spies. Why was it flying? This is war going on. Despite the conflict there commercial aircraft had been perpendiculared to fly over that area as long as they stayed above 32,000 feet. Overnight the entire space has been shut down to commercial craft. The state department had been warning against American passenger planes flying in other areas. Slightly different part. Now that entire area over where this took place has been shut down to all commercial aircraft. Thanks. Now U.S. Officials say it

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